A ball is moving with a speed v towards north, collides with an identical ball, moving with the same speed towards east. After the collision, the two balls stick together and move towards north –east. The speed of the combination is (a) 2v (b) 3v (c) v (d) v/2

A ball is moving with a speed v towards north, collides with an identical ball, moving with the same speed towards east. After the collision, the two balls stick together and move towards north –east. The speed of the combination is (a) 2v (b) 3v (c) v (d) v/2
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